High lift device for aircrafts due to supercirculation



Sept. 8, 1964 TOMlJlRO MORIYA 3,147,937 HIGH LIFT DEVICE FOR AIRCRAFTS DUE TO SUPERCIRCULATION Filed Oct. 50, 1961 2 Sheets-Sheet 1 Sept. 8, 1964 TOMlJ lRO MORIYA 3,147,937 HIGH LIFT DEVICE FOR AIRCRAFTS DUE TO SUPERCIRCULATION Filed Oct. 50, 1961 Y 2 Sheets-Sheet 2 F yfl. a

United States Patent 3,147,937 HIGH LIFT DEVICE FOR AIRCRAFTS DUE TO SUPERCIRCULATION Tomijiro Moriya, 35 Omiyarnae 6-chome, Suginami-ku, Tokyo, Japan Filed Oct. 30, 1961, Ser. No. 148,668 Claims priority, application Japan Nov. 8, 1960 6 Claims. (Cl. 244-42) The present invention relates to a high lift device for aircrafts due to supercirculation, and has for the principal object the provision of a high lift device for aircrafts due to super-circulation, for the purpose of remarkably shortening the distance required for taking off and landing of aircrafts and simultaneously of obtaining a remarkably wide speed range for performances in the air.

For accomplishing the object referred to above, according to the present invention, a high lift is contem plated to provide by imparting a supercirculation to wings. Said supercirculation can be obtained by means of special flaps and simultaneously by providing the flaps for deflecting stream lines on the trailing edge of wings, or by rounding the trailing edge of wings, and by ejecting a high velocity airjet from the trailing edge or from the inside roots of flaps.

As apparent from the foregoing description, the present invention is contemplated to propose one of the most efficient devices for providing high lift, the essentials thereof lying in that the occurrence of said supercirculation is perfected by constraining stream lines of ambient air around the wing to the position occupied by stream lines when the supercirculation occurs, by means of a flap hinged near the stagnation point for a theoretically maximum supercirculation, and simultaneously by forms and constructions of the trailing edge of wings, as well as by a high velocity jet, whereby the high velocity jet due to the opening and closing of said flaps is adapted to increase the supporting force for the weight of an aircraft and to serve as a thrust for propulsion of an aircraft.

Thus, the apparatus according to the present invention is provided with a special flap and is so constructed as to constrain stream lines to the position where a supercirculation occurs. Accordingly, a high lift can be provided. Furthermore, the vertical component of the thrust constitutes a part of the supporting force for the weight of an aircraft, bringing about a further advantage of becoming more effective.

Furthermore, the advantage referred to above can be also accomplished by an apparatus according to a modification of this invention, as follows: i

In the said apparatus, wherein a high velocity jet is effected at the trailing edge of the flap, the trailing edge of wing is rounded and simultaneously a high velocity air jet is ejected at the root of the flap instead of the trailing edge thereof with equivalent satisfactory results as referred to above.

In all the apparatus according to this invention referred to above, stream lines are constrained by a flap hinged near a stagnation point for a theoretically maximum supercirculation, to a position occupied by stream lines when the supercirculation occurs, either to eject air from the trailing edge of said flap or at the root of the flap for obtaining the maximum lift of an aircraft. Said maximum lift is not necessarily an absolutely inevitable element. It is of course possible to make any supercirculattion even below the said theoretical maximum lift.

From this point of view, according to a further embodiment of this invention, stream lines are constrained by means of flaps provided not only near the stagnation point for the theoretically maximum supercirculation, but also at any intermediate point between said stagnation point and trailing edge of a wing, to the position occupied ice by stream lines, when the supercirculation occurs so that the hinge point may be a stagnation point, whereby a high velocity jet of air is ejected from the trailing edge or the root of said flap, and the trailing edge of the wing is rounded to produce a supercircula-tion, and said airjet serves to complete the supercirculation when the flap is opened, and the vertical component of the airjet thrust contributes to support the weight of machine and simultaneously the horizontal component acts as a thrust for propulsion of an aircraft.

Further, detailed descriptions are given on the apparatus of the present invention as follows, with respect to the following drawings, of which FIGS. 1 to 3 represent transition states of stream lines occurring around a wing of an aircraft;

FIGS. 4 and 5 show means for constraining stream lines around a wing of an aircraft;

FIGS. 6 to 10 are theoretical illustrations for one embodiment of the present invention;

FIGS. 11 and 12 are theoretical illustrations of another embodiment of the present invention;

FIG. 13 is a theoretical illustration which serves to explain a further embodiment of this invention.

In those figures similar parts are represented with similar symbols. Notwithstanding, it should be noted that the present invention would never be limited by the following description, excepting of the patent claims as given later, but it is of course understood that numerous detailed alterations as well as modifications would be possible, of course, by those skilled in the art without departing from the scope and spirit of this invention.

When air flows relatively against the wing 1, stream lines 2 extending around said wing are usually as shown in FIG. 1, and accordingly, a circulation occurs so that the trailing edge 3 of said wing becomes a stagnation point.

When the circulation is increased, stream lines 2 would be as shown in FIG. 2 and the fore and aft stagnation points 4 and 5 would approach to each other with increasing the circulation.

Therefore, .if the circulation could be increased as in FIG. 3, until the fore and aft stagnation points coincide at 6, it would be regarded as a condition for the wing receiving a theoretical maximum lift. The present invention is contemplated to materialize such a condition.

To begin with, as in FIG. 4 stream lines are constrained at their positions by extending flap 7 from stagnation point 6 as shown in FIG. 3 in the direction of stream lines passing through the point 6. However, it is difiicult to constrain stream lines at their positions by an ordinary split flap alone and as a result a large wake 8 will occur as shown in FIG. 5.

In order to improve the disadvantage just-mentioned, first the trailing edge 3 of the wing is rounded as in FIG. 6 or another flap 9 is pivoted at the trailing edge of the wing as in FIG. 7 in order to facilitate stream lines to flow along the trailing edge, and to make the width of wake 8 narrower. Thereby, a considerable improvement is obtainable. In fact, however, this is not sufiicient to remove entirely the wake 8 and the width of wake 8 is still left unremoved to some extent and it is diflicult to reach a condition corresponding to that shown in FIG. 3.

When a high velocity air jet is ejected from the trailing edge of the flap 7 as shown in FIG. 8, the ejection of air inducing the ambient air to attract stream lines. In consequence, an ideal condition as shown FIG. 3 is approached and the theoretical maximum lift can be rea1- ized.

On the other hand, in order to attain the condition as shown in FIG. 3, according to another modification of the present invention, the trailing edge 3 of wing 1 is rounded as shown in FIG. 11 to facilitate flow of stream lines 2 along said trailing edge 3 and simultaneously a high velocity air jet is ejected from the root 11 of flap 7, thereby enabling to raise more satisfactory results above the apparatus referred to above. The flap root 11 comprises a tubular manifold member suitably journalled to turn in the bottom surface of the wing 1.

When a high velocity air jet is ejected from the stagnation point 6 along the inside surface of the flap as in FIG. 11, this air jet induces the ambient air to display an effect of drawing stream lines towards it and approaches the ideal condition illustrated in FIG. 3 and thus the theoretically highest lift can be approached. By so doing, not only a high lift can be obtained by a supercirculation, but a sort of VT OL characteristics can also be imparted to the lift by virtue of a vertical component of a reactional force caused by the jet, which enables a remarkable shortening of the taking-off and landing distance for aircrafts.

A flight performance as in ordinary aeroplanes is obtainable by closing the flap 7 after the taking-off of aircraft, and in this case the propulsive force is particularly advantageous with respect to the efliciency, construction and weight of the aircraft, because jets from flaps 7 are utilized directly as illustrated in FIGS. 9, 10 and 12, instead of propellers and jets as in jet planes.

On the other hand, the opening and closing of flaps during flight as well as the adjustment of a flap angle during flight enables a large range of the velocity of flight.

In the above-mentioned apparatus, stream lines are constrained by means of a flap, hinged near a stagnation point for a theoretically maximum supercirculation, to a position where a supercirculation occurs, for obtaining the maximum lift of an aircraft by ejecting a high velocity jet of air from the root of said flap. However, the said theoretically maximum lift of the aircraft is not necessarily to be an inevitable element. According to design specifications even below the theoretically maximum lift, a desired object can be sufiiciently accomplished. For this reason, in the device according to this invention, a flap may be arranged not only in the neighborhood of the stagnation point 6, but also at any intermediate point as shown in FIG. 13, between said stagnation point and the trailing edge 3 of the wing 1 for obtaining a considerably high lift.

What I claim is:

1. An airfoil having top and bottom surfaces, said airfoil having a leading edge and a trailing edge, said airfoil upon forward motion developing a circulation of air around the top and bottom of said airfoil surfaces from the leading edge to the trailing edge, said airfoil having stagnation points under said bottom surface according to the air circulation around said airfoil, said airfoil having a theoretical coincidence of stagnation points according to a maximum supercirculation of air around said airfoil, jet ejection means transversely positioned across said bottom airfoil surface at a predetermined position in relation to said theoretical coincidence of stagnation points, a flap depending from said jet ejection means whereby said jet ejection means develops a substantial equivalent of air circulation according to a maximum supercirculation, thereby materially contributing to the vertical lift component of the airfoil, said jet ejection means and said flap being integrally connected, and said jet ejection means serving as pivot means for said flap.

2. An airfoil as described in claim 1, wherein said jet ejection means is located intermediate said theoretical coincidence of stagnation points and said trailing edge.

3. An airfoil as described in claim 1, wherein said jet ejection means is an elongated tubular member with air jet openings directed toward said flap.

4. An airfoil as described in claim 1, wherein said jet ejection means comprises an elongated tube and said flap comprises a hollow body having one end joined to said tube and an opposite end opened, whereby a high velocity air jet is ejected from the trailing edge of the flap, said tube being journalled to turn in said bottom surface of said airfoil, whereby said flap may be moved downward to increase lift or moved upward to increase propulsive thrust.

5. An airfoil as described in claim 1, wherein said trailing edge of said airfoil is rounded, to thereby reduce the wake effect of constrained air streams around the airfoil.

6. An airfoil as described in claim 1, wherein said trailing edge of said airfoil includes an edge flap pivoted thereto.

References Cited in the file of this patent UNITED STATES PATENTS 2,912,189 POUi't NOV. 10, 1959 2,928,627 Johnson Mar. 15, 1960 3,016,213 Griswold Jan. 9, 1962 3,045,947 Bertin et al July 24, 1962 3,082,976 Dornier Mar. 26, 1963 3,102,704 Griswold Sept. 3, 1963 

1. AN AIRFOIL HAVING TOP AND BOTTOM SURFACES, SAID AIRFOIL HAVING A LEADING EDGE AND A TRAILING EDGE, SAID AIRFOIL UPON FORWARD MOTION DEVELOPING A CIRCULATION OF AIR AROUND THE TOP AND BOTTOM OF SAID AIRFOIL SURFACES FROM THE LEADING EDGE TO THE TRAILING EDGE, SAID AIRFOIL HAVING STAGNATION POINTS UNDER SAID BOTTOM SURFACE ACCORDING TO THE AIR CIRCULATION AROUND SAID AIRFOIL, SAID AIRFOIL HAVING A THEORETICAL COINCIDENCE OF STAGNATION POINTS ACCORDING TO A MAXIMUM SUPERCIRCULATION OF AIR AROUND SAID AIRFOIL, JET EJECTION MEANS TRANSVERSELY POSITIONED ACROSS SAID BOTTOM AIRFOIL SURFACE AT A PREDETERMINED POSITION IN RELATION TO SAID THEORETICAL COINCIDENCE OF STAGNATION POINTS, A FLAP DEPENDING FROM SAID JET EJECTION MEANS WHEREBY SAID JET EJECTION MEANS DEVELOPS A SUBSTANTIAL EQUIVALENT OF AIR CIRCULATION ACCORDING TO A MAXIMUM SUPERCIRCULATION, THEREBY MATERIALLY CONTRIBUTING TO THE VERTICAL LIFT COMPONENT OF THE AIRFOIL, SAID JET EJECTION MEANS AND SAID FLAP BEING INTEGRALLY CONNECTED, AND SAID JET EJECTION MEANS SERVING AS PIVOT MEANS FOR SAID FLAP. 